Hi, J.C. I have the original DHW coil plate sitting at work - I used it to trace out the replacement plate - I'll measure it at the thinnest part to see how bad it really was. My guess it was down to .125 at most in a spot or two.

The replacement plate I made from 1/4" A36 steel. I don't think I have any 5/16" plate - I'd have to go up to 3/8". I've not welded anything yet - I have to maneuver the boiler off the dolly and tip it up on end so I can weld horizontally after getting a nice bevel on the joint sides.

I'm going to guess that this boiler was welded originally with the SMAW process (a.k.a. "stick"). I can either use my friends flux-core Miller MIG or I've got an old Marquette 180 amp 'buzz-box'. Seems that for "pressure vessel" welding, 6011 rod for a root pass is used and then cap it off with something like 7014 or 7018.

Chris

Stick is what was used and is what should be used go with 7018 or 7024 stick better penetration better flow with the MiG you will or should mix with gas don't know what Miller model you have . 180 amp should do whatever you need to do or want to do. Is the buzz box a Ac & Dc or Just a single current model.

coal berner wrote:Stick is what was used and is what should be used go with 7018 or 7024 stick better penetration better flow with the MiG you will or should mix with gas don't know what Miller model you have . 180 amp should do whatever you need to do or want to do. Is the buzz box a Ac & Dc or Just a single current model.

The MIG is my buddy's from work - it's a 155 amp/240V flux core setup, which is a bit marginal for 1/4" and .035 flux core wire.

The stick welder is AC only, unfortunately, but it has multiple plug taps from 20A to 180A. Thanks for the advice on the rod - I'll check it out! I know 7018 is a low hydrogen rod that requires a rod oven to keep dry and special re-dry procedures if it's not kept dry.

coal berner wrote:7018 is a low hydrogen rod that requires a rod oven to keep dry and special re-dry procedures if it's not kept dry.

You are right about dry rods, but its not necessary to have a rod oven... Only for critical pipe and/or maybe structural have we ever stored rods in an oven, and that was all for power generation plant critical pipe welding.. So long as you keep them in a environment that is not mega humid you will be fine and the rods will perform wonderful... So, don't keep em in the basement if it has a dirt floor etc. Purchase a 'rodguard' tube holder for storage and you're good, and take note the color of the flux when they are brand new out the box, nice clean white and flux is hard to break off, if it starts to change color (darken up) and the flux chips off a bit easier then they're gettin old... Truth is in a perfect word all rods would be stored in an oven at all times, but thats just not the reality of things... So, have fun with that 7018, what a nice rod to run!!! Sounds like you're cookin' bacon when you're all dialed in right and runs smooth as glass!!!

I can honestly say that all the cussing, busted knuckles, ears and hair full of blasting grit, and being covered in green overspray was totally worth it today. I tossed in a couple of handfulls of split, scrap 2x6 pieces over two sheets of newspaper, lit it, waited a minute, and plugged it in. Kept the draft at "0" until the wood caught, and then opened it up a little. That was all it took for her to be off and runnin'.

Very very nice job you did on it. I just retired mine, but I always had the desire to spif it up nicely like yours. It served me well for 15 yrs, but when my cast iron boiler crapped out, I made the move to a Keystoker.

Btw, in case you haven't been around on of those, fyi;

Even with our dirty [mostly high sulphur bit] coal here [George's creek region], there is little to no smoke from the flue. I have found that they don't mind 6-10" of ash [clinker] in the box. If [big if] you have stoker coal made from the proper seam, when you clean out the clinkers, you can just pull the fine ash up on the fire, and it'll clinker up.

Good luck!

Btw, there are a large number of those stokers still in service around here. I believe that mine was put into service Sept 22, 1942!

6010 doesn't like AC current much, although you can probably get by. The 7024 will only run in the flat. If you have decent fit-up, you could probably do it all w/7018. It will run ok on AC, but better on DCEP [electrode positive, or old term = reverse]

Btw - with AC current and a consumable electrode, you have 50% of the heat on each side of the arc. With direct current, you have apx 70% of the heat on the negative side of the arc, and 30% on the positive side.

Related - with "TIG" [non consumable electrode], the opposite is true, so DCEN is normally used.

Davetin bangerformer welding instructor and AWS welding inspector[probably forgot 1/2 of what I once knew]

coal berner wrote:7018 is a low hydrogen rod that requires a rod oven to keep dry and special re-dry procedures if it's not kept dry.

You are right about dry rods, but its not necessary to have a rod oven... Only for critical pipe and/or maybe structural have we ever stored rods in an oven, and that was all for power generation plant critical pipe welding.. So long as you keep them in a environment that is not mega humid you will be fine and the rods will perform wonderful... So, don't keep em in the basement if it has a dirt floor etc. Purchase a 'rodguard' tube holder for storage and you're good, and take note the color of the flux when they are brand new out the box, nice clean white and flux is hard to break off, if it starts to change color (darken up) and the flux chips off a bit easier then they're gettin old... Truth is in a perfect word all rods would be stored in an oven at all times, but thats just not the reality of things... So, have fun with that 7018, what a nice rod to run!!! Sounds like you're cookin' bacon when you're all dialed in right and runs smooth as glass!!!

coal berner wrote:Stick is what was used and is what should be used go with 7018 or 7024 stick better penetration better flow with the MiG you will or should mix with gas don't know what Miller model you have . 180 amp should do whatever you need to do or want to do. Is the buzz box a Ac & Dc or Just a single current model.

The MIG is my buddy's from work - it's a 155 amp/240V flux core setup, which is a bit marginal for 1/4" and .035 flux core wire.

The stick welder is AC only, unfortunately, but it has multiple plug taps from 20A to 180A. Thanks for the advice on the rod - I'll check it out! I know 7018 is a low hydrogen rod that requires a rod oven to keep dry and special re-dry procedures if it's not kept dry.

Use the buzz box with the 7018 rod you will be fine but if you want a real nice smooth weld use the 7024 rod being your going to but the boiler on end you will have a nice flat area to weld 7024 need to be on a flat suface and a smooth even connection between the coil plate and back of the boiler wall . 7018 is all you real need for what your doing . No oven needed Just use a rod case and keep them cool and dry like the stove pipe off season storage

Today was welding day. I've got this week off for our annual summer shut down, and decided to get on it this morning early before it got too hot and I could work in the shade of the shop.

Getting the boiler off the dolly and into position so I could flip it up on end was interesting enough, and then I hooked a tow strap to my garden tractor and ran that to the big pipe "Tee" in the top boiler outlet. Gave it a little tug and she went right up on end. The trick will be getting it back.....might have to empty out the shop so I can drive the tractor in to pull the boiler back upright!

Anyway, I figured I had burned enough rods to have a pretty good idea of what I was doing. I beveled the patch plate as well as the boiler and tack welded some tabs on the patch plate so it would sit level in the hole. I took a deep breath and started the root passes with 6011 rod running 125 amps. A couple spots had a bit bigger gap than I wanted but an extra pass or two had it filled nicely. It wasn't the prettiest looking weld job, but I cleaned it up with the grinder and made sure I had a good area to weld the fill passes on. I then ran 7014 rod at 160 amps for the first fill pass and touched up a few areas with additional fill at 140 amps.

I've tried 7018 and 7018AC rod - the 7018 is hopeless, won't hold an arc, and the 7018AC tends to burn the rod up inside the flux and then quits. I don't know if it's the rod or the welder (or me), but some of the smaller AC welders just don't have the open circuit volts to keep 7018 rod (even the AC rod) going. Here's a couple of pics, one after the first fill pass and one after it's all done and cleaned up. Don't worry, I won't quit my day job to become a welder.

europachris wrote:Today was welding day. I've got this week off for our annual summer shut down, and decided to get on it this morning early before it got too hot and I could work in the shade of the shop.

Getting the boiler off the dolly and into position so I could flip it up on end was interesting enough, and then I hooked a tow strap to my garden tractor and ran that to the big pipe "Tee" in the top boiler outlet. Gave it a little tug and she went right up on end. The trick will be getting it back.....might have to empty out the shop so I can drive the tractor in to pull the boiler back upright!

Anyway, I figured I had burned enough rods to have a pretty good idea of what I was doing. I beveled the patch plate as well as the boiler and tack welded some tabs on the patch plate so it would sit level in the hole. I took a deep breath and started the root passes with 6011 rod running 125 amps. A couple spots had a bit bigger gap than I wanted but an extra pass or two had it filled nicely. It wasn't the prettiest looking weld job, but I cleaned it up with the grinder and made sure I had a good area to weld the fill passes on. I then ran 7014 rod at 160 amps for the first fill pass and touched up a few areas with additional fill at 140 amps.

I've tried 7018 and 7018AC rod - the 7018 is hopeless, won't hold an arc, and the 7018AC tends to burn the rod up inside the flux and then quits. I don't know if it's the rod or the welder (or me), but some of the smaller AC welders just don't have the open circuit volts to keep 7018 rod (even the AC rod) going. Here's a couple of pics, one after the first fill pass and one after it's all done and cleaned up. Don't worry, I won't quit my day job to become a welder.

P1010690.JPG

P1010696r1.jpg

The boiler top is only 575lbs just grab it at the end and flip it up on end Do you have a hoist or com along put a board down on the floor then lower the boiler onto it. Or with your tractor bucket and a chain hook the chain under the boiler lip or screw in a piece of black pipe into the returns with tees on the end of pipes and lower it with the chain

I did build an overhead "gantry" frame out of 2x4 and 2x6 lumber just wide enough for the boiler to sit within. This allowed me to strap up my ratchet hoist and hook it to the pipe "T" at the top of the boiler. That got the boiler off the dolly and onto the ground. Tractor + strap hooked to the "T" got the boiler on it's side for the welding.

Getting it back upright was actually a LOT easier than I thought. I had it upside down with one side propped up on a few wood blocks so I could scrape all the junk from the heat exchanger tubes. I probably cleaned 5 pounds of rust and old fly ash out of there, definitely glad I did it. I was able to tip it back on end with just a few pieces of pipe for leverage (so the round door hole was facing down again). I had a 2x6 under the door hole so it wouldn't dig into anything, and that allowed a good pivot point for me to grab the pipe "T" screwed into the top outlet hole again and just pivot it right back over upright. I was really surprised how easy it was. I then used my "gantry crane" to lift it back up and onto the dolly. I am certainly no strong-man being a 6'0" 175lb. engineer but I do OK for being 40.

I'll use the gantry again later to lift the boiler up on the base. That comes next after I clean the rust of the boiler and give it a coat of aluminum paint. Unfortunately I don't have a tractor with a loader nor anyone relatively close that has one. I keep trying to come up with enough excuses to get a little compact utility tractor/loader but just can't justify it.

I did build an overhead "gantry" frame out of 2x4 and 2x6 lumber just wide enough for the boiler to sit within. This allowed me to strap up my ratchet hoist and hook it to the pipe "T" at the top of the boiler. That got the boiler off the dolly and onto the ground. Tractor + strap hooked to the "T" got the boiler on it's side for the welding.

Getting it back upright was actually a LOT easier than I thought. I had it upside down with one side propped up on a few wood blocks so I could scrape all the junk from the heat exchanger tubes. I probably cleaned 5 pounds of rust and old fly ash out of there, definitely glad I did it. I was able to tip it back on end with just a few pieces of pipe for leverage (so the round door hole was facing down again). I had a 2x6 under the door hole so it wouldn't dig into anything, and that allowed a good pivot point for me to grab the pipe "T" screwed into the top outlet hole again and just pivot it right back over upright. I was really surprised how easy it was. I then used my "gantry crane" to lift it back up and onto the dolly. I am certainly no strong-man being a 6'0" 175lb. engineer but I do OK for being 40.

I'll use the gantry again later to lift the boiler up on the base. That comes next after I clean the rust of the boiler and give it a coat of aluminum paint. Unfortunately I don't have a tractor with a loader nor anyone relatively close that has one. I keep trying to come up with enough excuses to get a little compact utility tractor/loader but just can't justify it.

The paint inside will not last that long it will help keep the flyash from sticking hard to the inside for the first few cleaning but after a season or two the paint will be gone .

I've been busy the past few weekends trying to finish up this project before I'm wearing shorts again. It doesn't help that Blaschak is up to $375/ton out here, and my natural gas cost is down to $0.65/therm TOTAL cost. Nothing against NEPA, but it's time I spent my money on ILLINOIS coal.

The base design was finalized and fabricated from 1-1/2 x 3/16 angle and 13ga. sheet, welded together. Flue outlet is 6" with an access panel opposite for fly ash cleanout and a fire door on the front for clinker removal. I stuck the stoker in from the side so both doors would be on the front and I wouldn't be tripping over the stoker tubes.

I then painted the base with BBQ black Rustoleum, choosing the color simply because I couldn't get any other high temp paint in a can - everthing else was spray bombs and I didn't want to spray inside and it's way too cold to spray outside. I used a short nap trim roller and it worked most excellent.

Finally I plugged the stoker into the base, made up a fill panel (laying on top of the base in the picture) to close out the opening, and now I need to fill in around the retort and place the hearth. The base to pot heights worked out (not sure by accident or on purpose) so that a layer of brick as a floor leaves just enough height for a row of vertical brick all around (9") that fit under the angle iron top frame. I'll take pics when it's finished - it will be more clear then.

Today I need to go and blow a wad on 150' of 1" copper, fittings, uni-strut clamps, and pipe insulation. I've already got the uni-strut mounted to the basement concrete to route the water to the furnace plenum.

Controls will be handled by a CuBloc PLC using a National Instruments LM34 temperature sensor mounted into a homebrew thermowell. I'm not using any PID control - just simple on-off limit control at this point (basically an electronic version of a Honeywell) and the PLC will also function as the stoker idle timer. A second thermostat will be hooked to the main thermostat in the house - the R-W connections on the new stat hooked to the R-G connection on the main stat. Therefore the call for heat will activate the blower only. This will signal the PLC (using a 24VAC coil cube relay to close the 24VDC control circuit) to fire the circulator and a 24VAC solid state time delay relay that will delay the blower up to 60 seconds to allow the fan coil to get warm. I ran direct bury Ethernet cable along with the pex and I will mount a small indicator box by the thermostats with green (stoker ON) and red (alarm - outfire, overtemp, etc) LEDs for status using two of the remaining 3 wire pairs.

Later I can get fancy and add zones for either the boiler building/shop (if it needs additional BTU), the main house garage, or a separate basement loop with a big baseboard. The basement gets REALLY cold in the early spring when it's warm enough during the day the heat doesn't run much so all the cold air collects downstairs. I might also add a display and/or keypad to the PLC, but it's simply not needed at this point.

LsFarm wrote:Awesome job Chris.. you have that baby so pretty, you won't want to stoke it up with that nasty dirty bit coal.

Your work and install looks like a showroom model for retail customers to look at .. very nicely done.

Greg L

Thanks, Greg. Maybe I'll start a new revolution around these parts with "modern" coal heating. NEPA never forgot coal, but we sure did out here.

I think the stoker will take care of the soot issue that plagues hand firing bituminous, and having it separate from the house will take care of the rest. It can't be worse than carrying dripping bags of Blaschak through the house.

Just got back from my plumbing run. OMFG!!! 1" copper prices are INSANE!!! It probably would have been cheaper to run parallel 3/4" runs instead! The 1" is twice the cost of 3/4" for the pipe and the fittings are anywhere from 3x to 6x more expensive. It's just STUPID expensive comparing the two sizes. But it was either use 1" copper and a $75 circulator or 3/4" copper and a $225 circulator that uses 3x the electricity....